U.S. patent application number 12/481456 was filed with the patent office on 2009-12-17 for mobile station, base station, and method for uplink service.
This patent application is currently assigned to ELECTRONICS AND TELECOMMUNICATIONS RESEARCH INSTITUTE. Invention is credited to JUHEE KIM, Kyung Soo KIM.
Application Number | 20090310553 12/481456 |
Document ID | / |
Family ID | 41414701 |
Filed Date | 2009-12-17 |
United States Patent
Application |
20090310553 |
Kind Code |
A1 |
KIM; JUHEE ; et al. |
December 17, 2009 |
MOBILE STATION, BASE STATION, AND METHOD FOR UPLINK SERVICE
Abstract
The present invention relates to a mobile station, a base
station, and a method for an uplink service that provides a
high-speed data service between the base station and the mobile
station in a wireless communication system. A method for providing
an uplink service in a mobile station includes, after TCP data are
received from a base station, measuring a partial round trip time
which is a time until ACK which is a response to the received TCP
data is inputted into an uplink transmission MAC buffer,
transmitting information on the measured partial round trip time to
the base station, receiving resource allocation
information--unicast resource allocation information for
transmitting the ACK to the base station in the mobile
station--from the base station, and transmitting the ACK of the TCP
data received from the base station on the basis of the resource
allocation information to the base station.
Inventors: |
KIM; JUHEE; (Daejeon,
KR) ; KIM; Kyung Soo; (Daejeon, KR) |
Correspondence
Address: |
Jefferson IP Law, LLP
1130 Connecticut Ave., NW, Suite 420
Washington
DC
20036
US
|
Assignee: |
ELECTRONICS AND TELECOMMUNICATIONS
RESEARCH INSTITUTE
Daejeon
KR
Samsung Electronics Co., Ltd.
Suwon-si
KR
|
Family ID: |
41414701 |
Appl. No.: |
12/481456 |
Filed: |
June 9, 2009 |
Current U.S.
Class: |
370/329 |
Current CPC
Class: |
H04W 72/085 20130101;
H04W 72/0406 20130101 |
Class at
Publication: |
370/329 |
International
Class: |
H04W 72/04 20090101
H04W072/04 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 13, 2008 |
KR |
10-2008-0055624 |
Mar 31, 2009 |
KR |
10-2009-0027795 |
Claims
1. A method for providing an uplink service in a mobile station,
comprising: (a) after TCP data are received from a base station,
measuring a partial round trip time which is a time until ACK which
is a response to the received TCP data is inputted into an uplink
transmission MAC buffer; (b) transmitting information on the
measured partial round trip time to the base station; (c) receiving
resource allocation information--unicast resource allocation
information for transmitting the ACK to the base station in the
mobile station--from the base station; and (d) transmitting the ACK
of the TCP data received from the base station on the basis of the
resource allocation information to the base station.
2. The method of claim 1, wherein the resource allocation
information includes information on a unicast chance waiting timer
which is a time when the mobile station waits for a unicast uplink
access chance allocated from the base station after receiving a
request for transmitting the ACK from an upper hierarchy.
3. The method of claim 2, wherein the step (d) includes: (i)
starting driving the unicast chance waiting timer when the ACK of
the TCP data received from the base station is inputted into an
uplink transmission MAC buffer, and (ii) transmitting the ACK using
unicast uplink resource allocated from the base station when the
unicast uplink resource is allocated from the base station before
the unicast chance waiting timer is terminated.
4. The method of claim 3, wherein the step (d) further includes
(iii) transmitting the ACK to the base station in a wireless
section random access scheme when the unicast uplink resource is
not allocated from the base station until the unicast chance
waiting timer is terminated.
5. The method of claim 4, wherein the partial round trip time is
measured by analyzing a serial number of the TCP data received from
the base station and an ACK number that is requested to be
transmitted to the uplink transmission MAC buffer.
6. The method of claim 5, wherein the information on the partial
round trip time of step (b) includes information on an average and
a standard deviation of the partial round trip time, which are
measured by performing the step (a) multiple times.
7. The method of claim 6, wherein the step (c) is performed after
the step (a) is repeated a predetermined number of times when a
request is received from the base station, or when a report is
required due to modification of the information on the partial
round trip time.
8. A method for providing an uplink service to a mobile station in
a base station, comprising: (a) receiving information on a partial
round trip time--a time until ACK which is a response to TCP data
is inputted into an uplink transmission MAC buffer after the mobile
station receives the TCP data from the base station--from the
mobile station; (b) calculating a reception point of ACK of the TCP
data to be transmitted in future on the basis of information on the
partial round trip time and transmitting resource allocation
information--unicast resource allocation information for
transmitting the ACK to the base station in the mobile station--to
the mobile station; and (c) allocating a unicast uplink resource to
the mobile station at the reception point of the ACK after
transmitting the TCP data to the mobile station.
9. The method of claim 8, wherein the resource allocation
information includes information on a unicast chance waiting timer
which is a time of waiting for a unicast uplink access chance
allocated from the base station after the mobile station receives a
request for transmitting the ACK from an upper hierarchy.
10. The method of claim 9, wherein the information on the partial
round trip time in the step (a) includes information on an average
and a standard deviation of the partial round trip time.
11. The method of claim 8, wherein the step (b) includes: (i)
calculating a reception point of ACK of TCP data to be transmitted
in the future on the basis of the information on the average and
standard deviation of the partial round trip time, and (ii)
transmitting the resource allocation information to the mobile
station.
12. The method of claim 11, further comprising (d) cancelling
unicast uplink resource allocation for receiving a response to TCP
having a TCP number or less for the ACK received from the mobile
station when the ACK received from the mobile station is a response
to a TCP that is larger than an estimated TCP number.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims priority to and the benefit of
Korean Patent Application Nos. 10-2008-0055624 and 10-2009-0027795
filed in the Korean Intellectual Property Office on Jun. 13, 2008
and Mar. 31, 2009, the entire contents of which are incorporated
herein by reference.
BACKGROUND OF THE INVENTION
[0002] (a) Field of the Invention
[0003] The present invention relates to a mobile station, a base
station, and a method for an uplink service that provides a
high-speed data service between the base station and the mobile
station in a wireless communication system.
[0004] (b) Description of the Related Art
[0005] In a wireless communication system, when downlink TCP
traffic occurs from a base station to a mobile station, the mobile
station that receives a TCP packet transmits ACK of the received
packet to the base station, such that transmission of one TCP datum
is completed.
[0006] More specifically, the mobile station that receives the TCP
packet from the base station generates TCP ACK of the received TCP
packet and tries wireless section random access in order to
transmit the generated TCP ACK to the base station. Thereafter,
when the mobile station succeeds to access the base station, the
mobile station is allocated with a resource for transmission of the
TCP ACK from the base station and transmits the TCP ACK to the base
station by using the allocated resource.
[0007] At this time, in wireless section random access in which the
mobile station tries in order to transmit the TCP ACK to the base
station, since multiple users competitively access the base
station, code collision probability increases depending on the
number of users and traffic load. Further, in the case of failing
in initial wireless access, the mobile station repeatedly tries the
access, such that a network speed remarkably decreases.
[0008] The above information disclosed in this Background section
is only for enhancement of understanding of the background of the
invention and therefore it may contain information that does not
form the prior art that is already known in this country to a
person of ordinary skill in the art.
SUMMARY OF THE INVENTION
[0009] The present invention has been made in an effort to provide
a mobile station, a base station, and a method for an uplink
service having advantages of providing a high-speed data service
between the base station and the mobile station in a wireless
communication system.
[0010] An exemplary embodiment of the present invention provides a
method for an uplink service.
[0011] The method for providing an uplink service in a mobile
station includes: (a) after TCP data are received from a base
station, measuring a partial round trip time which is a time until
ACK which is a response to the received TCP data is inputted into
an uplink transmission MAC buffer; (b) transmitting information on
the measured partial round trip time to the base station; (c)
receiving resource allocation information--unicast resource
allocation information for transmitting the ACK to the base station
in the mobile station--from the base station; and (d) transmitting
the ACK of the TCP data received from the base station on the basis
of the resource allocation information to the base station.
[0012] Another embodiment of the present invention provides a
method for an uplink service.
[0013] The method for providing an uplink service to a mobile
station in a base station includes: (a) receiving information on a
partial round trip time--a time until ACK which is a response to
TCP data is inputted into an uplink transmission MAC buffer after
the mobile station receives the TCP data from the base
station--from the mobile station; (b) calculating a reception point
of ACK of the TCP data to be transmitted in the future on the basis
of information on the partial round trip time and transmitting
resource allocation information--unicast resource allocation
information for transmitting the ACK to the base station in the
mobile station--to the mobile station; and (c) allocating a unicast
uplink resource to the mobile station at the reception point of the
ACK after transmitting the TCP data to the mobile station.
[0014] According to the present invention, it is possible to
provide a mobile station, a base station, and a method for an
uplink service that provide a high-speed data service between the
base station and the mobile station in a wireless communication
system.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] FIG. 1 is a block diagram of a wireless communication system
according to an exemplary embodiment of the present invention.
[0016] FIG. 2 is a diagram illustrating an example of measurement
of a partial round trip time (PRTT) according to an exemplary
embodiment of the present invention.
[0017] FIG. 3 is a flowchart of a method for an uplink service
according to an exemplary embodiment of the present invention.
[0018] FIG. 4 is a diagram for illustrating resource allocation for
delayed acknowledgments scheme TCP ACK of a delayed acknowledgments
scheme in a base station 200 according to an exemplary embodiment
of the present invention.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0019] In the following detailed description, only certain
exemplary embodiments of the present invention have been shown and
described, simply by way of illustration. As those skilled in the
art would realize, the described embodiments may be modified in
various different ways, all without departing from the spirit or
scope of the present invention.
[0020] Accordingly, the drawings and description are to be regarded
as illustrative in nature and not restrictive. Like reference
numerals designate like elements throughout the specification.
[0021] In addition, throughout the specification, unless explicitly
described to the contrary, the word "comprise" and variations such
as "comprises" or "comprising" will be understood to imply the
inclusion of stated elements but not the exclusion of any other
elements.
[0022] In addition, the terms "-er", "-or", and "module" described
in the specification mean units for processing at least one
function and operation and can be implemented by hardware
components or software components and combinations thereof.
[0023] Throughout the specification, a round trip time (RTT) is a
time until TCP ACK which is a response to a corresponding TCP is
received from a mobile station after a base station transmits a TCP
packet to the mobile station.
[0024] Further, a partial round trip time (PRTT) is a time until
the received TCP packet is transmitted to a TCP hierarchy of the
mobile station and TCP ACK which is a response to the received TCP
is inputted into an uplink transmission MAC buffer from a point
when the mobile station receives the TCP packet from the base
station.
[0025] Hereinafter, a mobile station, a base station, and a method
for an uplink service that provide a high-speed data service
between the base station and the mobile station in a wireless
communication system according to an exemplary embodiment of the
present invention will be described in detail with reference to the
accompanying drawings.
[0026] A system and a method for an uplink service according to an
exemplary embodiment transmit and receive data by the frame unit in
order to support high-speed transmission of packet data in a
wireless section and operate based on OFDM/FDMA/TDD wireless
transmission schemes.
[0027] FIG. 1 is a block diagram of a wireless communication system
according to an exemplary embodiment of the present invention.
[0028] Referring to FIG. 1, the wireless communication system
according to an exemplary embodiment of the present invention
includes a mobile station 100, a base station 200, and an access
router 300. The components of FIG. 1 will be described below.
[0029] The mobile station (MS) 100 includes a transceiver 110, a
TCP ACK generator 120, a report processor 130, a unicast operator
140, and a controller 150. The mobile station 100 transmits TCP ACK
to the base station 200 on the basis of information included in a
"resource allocation information message" received from the base
station 200. The components of the mobile station 100 will be
described below.
[0030] The transceiver 110 transmits a partial round trip time
(PRTT) report message generated in the report processor 130 to the
base station 200 and receives the "resource allocation information
message" received from the base station 200.
[0031] The TCP ACK generator 120 generates TCP ACK which is a
response to a TCP packet received from the base station 200.
[0032] The report processor 130 includes a measurement unit 131, a
calculation unit 132, and a message generation unit 133. The report
generator 130 transmits the "PRTT report message" including an
average and a standard deviation of a measured partial round trip
time (PRTT) to the base station 200 through the transceiver 110.
The components of the report processor 130 will be described
below.
[0033] The measurement unit 131 measures the partial round trip
time.
[0034] FIG. 2 is a diagram illustrating an example of measurement
of a partial round trip time (PRTT) according to an exemplary
embodiment of the present invention. The mobile station 100
measures the partial round trip time (PRTT) by analyzing a serial
number of a TCP segment received from the base station 200 and an
ACK number requested to be transmitted for a transmission MAC
buffer.
[0035] However, since ACK is delayed by time-out of a delayed
acknowledgment scheme TCP which responds to several data segments
in single ACK, the partial round trip time (PRTT) that consumes 200
msec or more may be excluded from a measurement sample.
[0036] FIG. 2A illustrates an example of measurement of a partial
round trip time (PRTT) in a general scheme, and FIG. 2B illustrates
an example of measurement of a partial round trip time (PRTT) in a
delayed acknowledgment scheme.
[0037] Referring to FIG. 2A, the mobile station 100 transmits, from
a point of receiving a downlink TCP segment (SN:1) at an MAC/PHY
hierarchy from the base station 200 through a wireless
communication network, the corresponding downlink TCP segment
(SN:1) to a TCP hierarchy, and measures a time until TCP ACK (Send
ACK 2) corresponding to a response of the segment is inputted into
a uplink transmission MAC buffer.
[0038] Referring to FIG. 2B, in accordance with information
previously set by the delayed acknowledgment scheme, the mobile
station 100 transmits, from the point of receiving the downlink TCP
segment (SN:1) at the MAC/PHY hierarchy from the base station 200
through the wireless communication network, the corresponding
downlink TCP segment (SN:1) to the TCP hierarchy, and measures a
time until TCP ACK (Send ACK 3) corresponding to a response of the
segment is inputted into the uplink transmission MAC buffer.
[0039] The calculation unit 132 calculates an average and a
standard deviation of the partial round trip time (PRTT), which are
measured when the partial round trip time (PRTT) is repeated at a
predetermined number of times (N.sub.measurement) in the
measurement unit 131.
[0040] The message generation unit 133 generates a "PRTT report
message" including a service connection ID, and the average and
standard deviation of the measured partial round trip time
(PRTT).
[0041] The unicast operator 140 includes a determination unit 141.
When the unicast operator 140 receives information on "receiving a
request for transmission of the TCP ACK from an upper hierarchy"
from the TCP ACK generator 120, the unicast operator 140 starts
driving a unicast chance waiting timer (T.sub.waiting) and waits
for a unicast uplink access chance.
[0042] The determination unit 141 determines whether or not the
uplink access chance is allocated until the unicast chance waiting
timer (T.sub.waiting) is terminated.
[0043] When the uplink access chance is acquired before the unicast
chance waiting timer (T.sub.waiting) is terminated, the TCP ACK is
transmitted by using the allocated resource. On the contrary, when
the uplink access chance is not acquired until the unicast chance
waiting timer (T.sub.waiting) is terminated, uplink data
transmission can be tried by using wireless section random access
like a known best-effort service scheme.
[0044] The controller 150 controls operations of the transceiver
110, the TCP ACK generator 120, the report processor 130, and the
unicast operator 140.
[0045] The base station (BS) 200 includes a transceiver 210, a
calculator 220, a message generator 230, a resource allocator 240,
and a controller 250. The base station 200 calculates a reception
point of the TCP ACK on the basis of the "PRTT report message"
received from the mobile station 100, and transmits information on
the reception point of the TCP ACK to the mobile station 100. The
components of the base station 200 will be described below.
[0046] The transceiver 210 receives the "PRTT report message" from
the mobile station 100, and transmits the "resource allocation
information message" generated in the message generator 230 to the
mobile station 100.
[0047] The calculator 220 calculates an occurrence point of uplink
traffic on the basis of the "PRTT report message" received from the
mobile station 100. That is, the calculator 220 calculates the
occurrence point of the uplink traffic from the mobile station 100
to the base station 200 after downlink TCP traffic is serviced from
the base station 200 to the mobile station 100.
[0048] More specifically, the calculator 220 calculates a reception
point of the TCP ACK with respect to a TCP segment to be
transmitted and the reception point of the TCP ACK can be
calculated as shown in Equation 1.
Uplink access estimation frame number=Current frame
number+N.sub.offset N.sub.offset=Average value of
PRTT+(.alpha..times.Standard deviation value of PRTT) [Equation
1]
[0049] The message generator 230 generates the "resource allocation
information message". At this time, the "resource allocation
information message", as information on unicast resource allocation
for transmitting the ACK from the mobile station to the base
station in the future, includes information on the "service
connection ID" and the "unicast chance waiting timer
(T.sub.waiting)" waiting for the unicast uplink access chance after
the mobile station 100 receives the request for transmitting the
TCP ACK from the upper hierarchy.
[0050] The resource allocator 240 allocates a unicast uplink
resource (i.e., bandwidth) to the mobile station 100 at the
occurrence point of the uplink traffic calculated in the calculator
220.
[0051] The controller 250 controls operations of the transceiver
210, the calculator 220, the message generator 230, and the
resource allocator 240.
[0052] An access router 300 performs mobility control and a packet
router function of the mobile station 100.
[0053] Hereinafter, a method for an uplink service according to an
exemplary embodiment of the present invention will be described in
detail with reference to the accompanying drawings.
[0054] FIG. 3 is a flowchart of a method for an uplink service
according to an exemplary embodiment of the present invention.
[0055] Referring to FIG. 3, when a TCP packet (PDU with TCP
segment) is successively transmitted from a base station 200 to a
mobile station 100 (FN:0), the mobile station 100 generates TCP ACK
of the received TCP packet (FN:1) and measures a "partial round
trip time (PRTT)" (FN:2).
[0056] Thereafter, the mobile station 100 tries wireless section
random access to the base station 200 in order to transmit the TCP
ACK (FN:3). Thereafter, CDMA allocation IE data are transmitted to
the mobile station 100 through an uplink map (UL-MAP) message in
the base station 200 (FN:4), and the mobile station 100 transmits a
bandwidth request allocation header (BR-Req. Header) to the base
station 200 (FN:5).
[0057] Thereafter, the base station 200 that receives the bandwidth
request allocation header (BR-Req. Header) allocates the resource
by transmitting unicast burst allocation to the mobile station 100
through the uplink map (UL-MAP) message (FN:6) and the mobile
station 100 transmits the previously generated TCP ACK to the base
station, such that transmission of the TCP packet is terminated
(FN:7).
[0058] When steps of FN:0 to FN:7 are repeated at a predetermined
number of times (Nmeasurement), the mobile station 100 calculates
an average and a standard deviation of the measured partial round
trip time (PRTT) (FN:8).
[0059] Thereafter, the mobile station 100 generates a PRTT report
message including a service connection ID, and the average and
standard deviation of the measured partial round trip time (PRTT)
(FN:9) and transmits the generated PRTT report message to the base
station 200 (FN:10).
[0060] At this time, the PRTT report message may be transmitted
after steps of FN:0 to FN:7 are repeated the predetermined number
of times (Nmeasurement), or the PRTT report message may be
eventually transmitted when a request is received from the base
station 200 or by a report necessity in accordance with a
statistical change of the partial round trip time (PRTT).
[0061] The base station 200 that receives the PRTT report message
calculates a reception point of the TCP ACK with respect to the TCP
segment to be transmitted (FN:11), and transmits a "resource
allocation information message" including information on a "unicast
chance waiting timer (Twaiting)" waiting a unicast uplink access
chance to the mobile station 100 after the mobile station 100
receives a request for transmitting the TCP ACK from an upper
hierarchy (FN:12).
[0062] Thereafter, when the TCP packet (PDU with TCP segment) is
successively transmitted from the base station 200 to the mobile
station 100 (FN:13) and the mobile station 100 receives the request
for transmitting the TCP ACK from the upper hierarchy (FN:14), the
mobile station 100 starts driving the unicast chance waiting timer
(Twaiting) and waits for the unicast uplink access chance (FN:15).
At this time, a time-out time of the unicast chance waiting timer
(Twaiting) does not exceed 500 ms which is an ACK transmission
limit time in the TCP.
[0063] When an uplink access estimation frame is reached, the base
station 200 allocates the unicast uplink access chance to the
mobile station 100 (FN:16). The size of the allocation resource is
determined by negotiation at the time of establishing service
connection so as to transmit the TCP ACK. When a wireless resource
is not sufficient for the TCP ACK in the estimation frame, the base
station 200 can allocate the uplink resource for a BW-REQ header or
allocate resource for the TCP ACK in the next frames.
[0064] The mobile station 100 that acquires the uplink access
chance transmits relevant TCP ACK (FN:17).
[0065] Meanwhile, the mobile station 100 that does not acquire the
uplink access chance until the unicast chance waiting timer
(Twaiting) is terminated may attempt transmitting the uplink data
by using the known wireless section random access.
[0066] FIG. 4 is a diagram for illustrating resource allocation for
delayed acknowledgments scheme TCP ACK in a base station 200
according to an exemplary embodiment of the present invention.
[0067] Referring to FIG. 4, after the base station 200 transmits
segments of serial numbers 1 to 4, the base station 200 allocates
corresponding wireless resources for ACK corresponding to the
segments, respectively, after the Noffset frame of Equation 1. At
this time, {circle around (k)} is the number of TCP ACK that is
estimated to be received.
[0068] However, the base station 200 grants a unicast chance to the
mobile station 100 (the number of the TCP ACK that is estimated to
be received is 2 (resource allocation of {circle around (2)})). In
this case, when the number of the TCP ACK received from the mobile
station 100 is 3, the base station 200 determines the delayed
acknowledgments scheme and cancels up to the unicast resource
allocation in which the reception estimation number of the TCP ACK
to be allocated is 3 (resource allocation of {circle around (3)} is
cancelled).
[0069] That is, the base station 200 cancels allocation of a future
unicast uplink access chance for TCP ACK having a serial number
(SN) which is equal to or smaller than the ACK number received from
the mobile station 100. Therefore, it is possible to avoid
unnecessary waste of the wireless resource at the time of the TCP
operation using the delayed acknowledgments scheme.
[0070] Parameters negotiated at the time of establishing uplink
service connection in order to excellently perform the operation
according to an exemplary embodiment of the present invention may
include i) the service connection ID of relevant downlink, ii) the
size of a service data unit at the time of allocating the unicast
resource, iii) the unicast chance waiting timer value
(T.sub.waiting), and iv) the number of times (N.sub.measurement) to
try measuring the partial round trip time.
[0071] A base station according to the present invention calculates
an occurrence point of uplink traffic from a mobile station after
transmitting downlink TCP traffic data to the mobile station and
appropriately allocates a unicast uplink resource for the mobile
station to a calculated time section, such that the mobile station
can instantly transmit uplink traffic without using wireless
section random access.
[0072] Accordingly, according to the present invention, it is
possible to solve a problem in that a round trip time increases at
the time of transmitting and receiving packet data between the base
station and the mobile station due to a wireless access
characteristic of a best-effort service and provide a speed
enhancement effect while backward scheduling in the base
station.
[0073] The exemplary embodiments of the present invention are not
only implemented through the apparatus and method, but may be
implemented through a program that realizes functions corresponding
to constituent members of the exemplary embodiments of the present
invention or a recording medium in which the program is recorded.
The implementation will be easily implemented by those skilled in
the art as described in the exemplary embodiments.
[0074] While this invention has been described in connection with
what is presently considered to be practical exemplary embodiments,
it is to be understood that the invention is not limited to the
disclosed embodiments, but, on the contrary, is intended to cover
various modifications and equivalent arrangements included within
the spirit and scope of the appended claims.
* * * * *